You shouldn't confuse hot pixels with normal high ISO noise. There are three options linked to noise on Olympus cameras :

I am not referring to general high ISO noise, but pixel problems like in the attached pic (see full size). Pixel mapping did heal some of it, but to me it "seems" recurring...

Are you using auto noise reduction? This should make the problem almost unnoticeable (unless you take lots of long exposures of blackness...). That and pixel mapping, a nice feature for the camera to have, should really take care of it. I don't see wha you're referring to above, but I'm on a very small screen right now.